Density Functional Study on the Growing Pattern of BnPm Clusters (n = 1 - 4, m = 1 - 4, n + m ≤ 5)

V. FERRARESI CUROTTO; R. PIS DIEZ

Ouro Preto, Minas Gerais

Simposio; Simpósio Brasileiro de Química Teórica (16.: 2011: Ouro Preto, 2011); 2011

Universidade Federal de Ouro Preto

Semiconductors formed by group 13/15 elements have increasing importance due to the potential application in the preparation of thin films for electronic devices [1]. The interest in the study of BP atomic clusters is based on the fact that the application in thin films requires a profound understanding of properties at atomic level as well as the growing pattern followed by the aggregates. Results obtained for clusters up to five atoms are reported, with emphasis on the growing pattern followed by the aggregates. B/P aggregates were studied with tools from density functional theory (DFT); using the B3LYP hybrid exchange and correlation functional [2], with cc-pVTZ triple-ζ basis functions [3], as implemented in the Gaussian 03 program [4]. Equilibrium geometries were obtained starting from the BP dimer and adding up boron and phosphorus atoms to grow the aggregates. The increase in the binding energy per atom was used to evaluate the growing. The preferred growing pattern was found to be BP (3A) → BPB (2A) → BBBP (3A) → BBPBB (4A). Molecular electrostatic potentials (MEP), spin densities and charges derived from electrostatic potentials (ESP charges), were calculated to get a quantitative picture of the whole process. Our results, obtained from calculations on clusters of up to five atoms, appear to indicate that B-P clusters tend to grow following a non planar pattern, preferring zones in which ESP charges are large. Moreover, B-B unions are favored over B-P and P-P unions. [1] S. Nakamura, In Proceedings of International Symposium on Blue Laser and Light Emitting Diodes; A. Yoshikawa, K. Kishino, M. Kobayashi, T. Yasuda, Eds.; Chiba University Press: Chiba, 1996; p 119. [2] A. D. Becke and J. Chem. Phys. 98 (1993) 5648; C. Lee, W. Yang and R. G. Parr, Phys. Rev. B 37 (1988) 785. [3] T. H. Dunning, Jr. J. Chem. Phys. 90 (1989) 1007; T. H. Dunning, Jr. J. Mol. Struct. 388 (1996) 339. [4] M. J. Frisch, et al., Gaussian, Inc., Wallingford CT, 2004, Gaussian 03, Revision D.01.